The ability of arboviruses to persist in novel environments is undoubtedly a function of the rapid adaptability of their RNA genomes, as illustrated by the large number of WNV(18, 72), SLE (71)and JEV (89) genotypic variants that exist in new ecosystems. In addition, considerable genetic data demonstrates a viral genetic component for virulence potential for SLEV (9, 81), WNV (5) and JEV (47, 84) strains. This genetic variability necessitates the identification of conserved viral genetic sequences that can be utilized in the development of genetic tools for viral identification and characterization. In addition to highly specific detection methodologies, new diagnostic assays capable of detecting a wide range of introduced arboviral agents are also needed. Generation of fundamental genetic sequence data on a number of potentially introduced arboviral agents will allow for the targeting of different regions of viral genomes for the development of cross-reactive rapid amplification methodologies that will aid in the improvement of existing surveillance and predictive emergence models for the prevention of human and veterinary disease from introduced viral agents. In human or animal samples where viral genome and antigen may no longer be present, the detection of antibodies can indicate the presence of an introduced agent. Currently, rapid serologic screening assays are non-specific, and the more specific confirmatory assays (e.g., neutralizing antibody assays) require many days of culture and specialized biocontainment laboratories. Rapid (sameday), highly specific serologic assays capable of detecting arboviral reactive irnmunoglobulin, without the need to work with the actual agent, are urgently needed. Under the direction of Dr. Carol Glaser, the VRDL performs standard plaque and other assays for arboviruses of public health importance, such as WNV and SLEV. In the proposed collaborative studies, the VRDL, along with UC Davis investigators, will compare the new molecular assays to standard assays, and will assist in disseminating use of the new assays throughout the California public health system.